The optic nerve head in young adult rodents contains 10 different cell types, each which secretes extracellular vesicles. We isolated rat optic nerve heads aand dissociated them in cell culture, in triplicate, from n=20 rat optic nerve heads/culture and collected and purified the extracellular vesicles (EVs)from the conditioned medium of the first 3 platings of the primary cell cultures. We performed proteomic analysis of the EVs using a variety of techniques EVs were then analyzed by both western analysis and HPLC-tandem MS/MS analysis, and proteomic analysis performed and peptides compared against a human protein database.